LeetCode OJ 之 Excel Sheet Column Number （excel表格列号）

题目：

Related to question Excel Sheet Column Title

Given a column title as appear in an Excel sheet, return its corresponding column number.

For example:

    A -> 1    B -> 2    C -> 3    ...    Z -> 26    AA -> 27    AB -> 28 

思路：

26进制的计算。

代码：

class Solution {public:    int titleToNumber(string s)     {        int result = 0;        int len = s.size();        for(int i = 0 ; i < len ; i++)        {            result = result * 26 + (s[i] - 'A' + 1)  ;        }        return result;    }};